In Madagascar, two seasons are recognized: a hot, rainy season from November to April and a cooler, dry season from May to October. The east coast has a sub-equatorial climate driven by easterly trade winds, along with the heaviest and most consistent rainfall, with a maximum of 3,700 mm annually. The west coast of the country is generally drier and is subject to significant coastal erosion. The southwest and the extreme south are semi-desert environments, receiving less than 800 mm of rainfall annually. The average annual temperatures vary between 23°C and 27°C along the coast and between 16°C and 19°C in the central mountains.
- There is clear evidence that temperatures have increased by 0.2°C over northern Madagascar and by 0.1°C over southern Madagascar.
- Between 1961 and 2005, 17 of the 21 weather stations recorded statistically significant increases in daily minimum temperatures across all seasons, and several stations indicated increased daily maximum temperature trends.
- The character of rainfall across Madagascar has changed significantly, although no obvious trend in rainfall can be surmised from the available record.
- A reduction in winter and spring rainfall has been detected in most parts of the country.
- In the central and east coastal regions, rainfall was on a steady decline between 1961 and 2005, accompanied by increases in the length of dry spells.